Add ARMv9.2-a arch option.

Bug: 364383722
Test: presubmit
Change-Id: Ica7266f6dbac490836f94f7e19685383aba2749f
diff --git a/android/arch_list.go b/android/arch_list.go
index f1289a3..2937092 100644
--- a/android/arch_list.go
+++ b/android/arch_list.go
@@ -159,6 +159,9 @@
 		"armv9-a": {
 			"dotprod",
 		},
+		"armv9-2a": {
+			"dotprod",
+		},
 	},
 	X86: {
 		"amberlake": {